99 Chevy 3500 HD (CK) 6.5 to dmax

[MaxPF]

i put 11,000 on the truck since i got it(86,000 on the ODO when i got it).. 95% loaded did all the basic upgrades except harmonic balancer repalcement.... upon removal i did find out the engine has been opened up before i got it and straight water came out for coolant...the history of it, i have no clue..

That sucks.

putting an allison in would increase cost some 2-3000 between buying tranny tcm drive shafts etc also the allison has close to 200lb on the 4l80 deeper 1st gear(3:1 vs 2.48) and taller overdrive (.70 vs .75)

The gearing is the biggest advantage with the Ally. The reverse gear is especially nice when backing a trailer. Weight difference is 170lbs, and there is a reason the Ally weighs that much more - the internals dwarf those of the 4L80.

honestly i can buils a 4l80e to handle 400hp cheaper then a allison and still be lighter... shift kits dont work on either long term.. 3k to put an allison in pluse another 1700 in parts for basic upgrade or 2500 in the 4l80 having someone do it with dyno test that i already have or toss in another 6-800 for a used 4l80 and have it built..... and save wieght.

It's false economy for what you are doing. All an otherwise healthy 6 speed Allison would need is a Transgo SK Jr. and a Transgo converter valve. A better converter wouldn't hurt, but you could get by without it. At the 400HP level that is a 200,000+ mile transmission. The 4L80E will not last nearly as long doing what you do. It simply doesn't have the clutch area, and you're likely to kill the OD sprag with the DMax's torque. There IS a very good reason GM derated the DMax when it was backed by the 4L80E. You can beef up some stuff in it, but the OD sprag is what it is, and unlike the Dodge 47/48's, nobody ever bothered making better upgrade parts for the 4L80E for DMax use because everyone used the Ally.

I'm just trying to keep you from doing stuff twice and spending more money in the long run. You're truck is a working truck, and there is no better transmission for that use than the Allison.

 

[2wpuller]

I would vote for the allison.Way better in the long run.
OD is .62 atleast in mine.
Dale

 

[malibu795]

It's false economy for what you are doing. All an otherwise healthy 6 speed Allison would need is a Transgo SK Jr. and a Transgo converter valve. A better converter wouldn't hurt, but you could get by without it. At the 400HP level that is a 200,000+ mile transmission. The 4L80E will not last nearly as long doing what you do. It simply doesn't have the clutch area, and you're likely to kill the OD sprag with the DMax's torque. There IS a very good reason GM derated the DMax when it was backed by the 4L80E. You can beef up some stuff in it, but the OD sprag is what it is, and unlike the Dodge 47/48's, nobody ever bothered making better upgrade parts for the 4L80E for DMax use because everyone used the Ally.

I'm just trying to keep you from doing stuff twice and spending more money in the long run. You're truck is a working truck, and there is no better transmission for that use than the Allison.

allison would be nice..the reality for me to swap in a stock allison will cost me close to 4,000 including buying a tranny.

i will still be using the same amount of power with the dmax that i used in the 6.5 for right now it will handle what i am doing just fine.

theres a good possibility i will just swap a Eaton fuller over driver 6 speed in the truck

 

[malibu795]

dale 5th is .7 and 6th is .62 on the allison

 

[MaxPF]

allison would be nice..the reality for me to swap in a stock allison will cost me close to 4,000 including buying a tranny.

I have 2800 in mine, and that includes having to get a second donor trans because the first one was f**ed up from some idiot flat towing it. It also includes a swapped bellhousing, transgo SK Jr. and converter calve hits, TCM, and wiring harness. I have more money into mine as well because I had to get extra stuff t swap it behind a Cummins. Putting it behind a DMax is plug-n-play.

With the Ally there would be no need to "upgrade" to a Fuller later on

dale 5th is .7 and 6th is .62 on the allison

5th is .71, 6th is .61.

1st - 3.10
2nd - 1.81
3rd - 1.41
4th - 1.00
5th - .71
6th - .61
Rev - 4.49

 

[malibu795]

I have 2800 in mine, and that includes having to get a second donor trans because the first one was f**ed up from some idiot flat towing it. It also includes a swapped bellhousing, transgo SK Jr. and converter calve hits, TCM, and wiring harness. I have more money into mine as well because I had to get extra stuff t swap it behind a Cummins. Putting it behind a DMax is plug-n-play.

With the Ally there would be no need to "upgrade" to a Fuller later on

outside the tranny itself. throw in another 1000-1500 for new driveshaft, tranny lines from 3/8 to 5/8 redo the parking brake (tail shaft mounted) and you are at 4000-4500 in the swap.

a 2wd allsion near me in decent condition is in the 2000-2500 range for a 5 speed

 

[LReiff]

outside the tranny itself. throw in another 1000-1500 for new driveshaft, tranny lines from 3/8 to 5/8 redo the parking brake (tail shaft mounted) and you are at 4000-4500 in the swap.

a 2wd allsion near me in decent condition is in the 2000-2500 range for a 5 speed

A few weeks ago I sold a good condition 2wd 6 spd with the pcm and partial wire harness for $800. I also have a 2wd 5 spd listed here for that...might take less.

 

[malibu795]

A few weeks ago I sold a good condition 2wd 6 spd with the pcm and partial wire harness for $800. I also have a 2wd 5 spd listed here for that...might take less.

thanks i will keep it in mind. i dont have the money to swap things over.. been down for 4 weeks, i need to get moving even if that means pulling little more fuel out of the dmax.. im fine with that... even at same power level dmax is leaps and bounds ahead of the 6.5 in efficentcy

 

[MaxPF]

A few weeks ago I sold a good condition 2wd 6 spd with the pcm and partial wire harness for $800. I also have a 2wd 5 spd listed here for that...might take less.

This ^ I got my first 6 speed for $1500 with 30k miles on it, and the second one with 60k minus bellhousing for $500.

When I say $2800, I mean with everything.

 

[2wpuller]

The web site I printed the info from had .62 I went back to it today and it was .61 so they changed it after I printed it out.Thank for the correction.

Dale

 

[malibu795]

typed in fso6406 and the nv5600 to fs6406 on cf came up.... hmmmm

 

[LReiff]

typed in fso6406 and the nv5600 to fs6406 on cf came up.... hmmmm

That is alot of reading, but some very good info!

 

[malibu795]

Took me 4 hours plus the 9 pages of similar thread on pirate

 

[rayjon]

nice swap, nice choice in trucks... supprized how light yours is,

I have a 95 3500hd crew cab, with a 5.9 cummins swap and a nv4500, 3.54 rear gears and it weighs over 8500lbs with a skirted flatbed.

I do wish gm has kept building that chassis it takes almost 3k lbs on the rear of mine to to touch the overloads.. and the brakes are better than the ford 450/550's and since the box vans/motorhomes used the same stuff its all dirt cheep...

FYI..

if you look at the fullers, take a look at the rto6610, its a small case 10 speed and will fit in your tunnel, there is a guy over in napa ca, that has one like yours with a service box with a cummins swap and a rt613 (same trans different splitter on the back) and it fits clean..(he grosses 18k on the truck alone. and for what you do would give you alot of options overdrive is .80 in them.. also allows you to go to a 1550 driveline, jesse at high angle driveline can get the yoke for the dana 80 for a 1550, then all you have to do is shorten the shaft off the truck you get the trans from.... I have found the trans for less than a grand in good shape. figure it will cost another grand it parts and clutch..

when my nv4500 dies this is the way I am going...

 

[malibu795]

ray couple people have mention the rt6610. at max gross is 32k with my setup. when i drove big trucks with 10 speeds i rarely used 1-3 i was always starting out in 4th even with full gross (80k) so even with 4.1 low gear on a 6406/8406 3-6gears are almost identical to the 4l80 gear set thats in there now. even if i dropped from 4.63 to 4.1 the only time i would be useing 1st or 2nd would be parking/ manuvering the extra gears sets would be useless to me. IMO if i am not going to use it often then why put in/on the truck, nickle and dime pounds add up.

the 6406 weighs ~350lb which is lighter then the 6610(iirc its twin countershaft) and the allison 1000 plus i wouldnt have to mess with air lines/tanks/dryer either to run the range shifter.

 

[chevota84]

Sent from my DROID X2 using Xparent Blue Tapatalk 2

 

[malibu795]

done well basicly its starts and moves on its own now. tranny is in limp mode 2nd/reverse
tach, speedo, OP, ECT need connected got a P2510 code.. out side disabling EGR, VATS i havent touched the stock van tune.. drove the truck to retrive my trailer (8 miles away) i will say that running in 2nd gear the truck moves 10x better then the 6.5 did in 1st with just a 6400lb trailler hooked to the back. the 99 is currently loaded up on the trailer hooked to my 75 headed to the dealer first thing to correct the TCM issue( its brand spanking new, original got compacted by a telephone pole) then go weigh it since pilot scale is just down the road. the custom engine mounts definently transfers more noise and vibration to the frame. im expecting it to with in 150lb of the old weight of 4000/2400

i will post video some time tomorrow..

 

[rayjon]

The rto6610 weighs 450 give or take light for a twin countershaft.. the main advantage for you is gas mileage running with an empty trailer. If you run 3.54 gears with an rto it puts you under 2200 rpm at 70mph..

I really like what you have done so far, I wish gm had built the truck that way ,

I really like mine rides good, stops good and works... Great chassis just a crappy diesel with a 6.5..but you fixed that..

Here"s mine

 

[malibu795]

Wish i had a crew cab version.. weight is an issue being a hotshot..weighed the truck today gained 30lb over the 6.5 setup..the fs6406 is 350lb with a .78 od

 

[MaxPF]

Wish i had a crew cab version.. weight is an issue being a hotshot..weighed the truck today gained 30lb over the 6.5 setup..the fs6406 is 350lb with a .78 od

:umno: FS6406 weighs 365lbs and has no overdrive.